Fighting drought with apple rootstocks
By Giulia Maria Marchetti

As climate change intensifies, rising temperatures and prolonged droughts threaten agricultural productivity, making water-efficient crops more important than ever. Agricultural research is becoming essential to improve water use and ensure sustainable fruit production under increasingly challenging environmental conditions.
The Free University of Bozen-Bolzano is doing its part. Anna-Lena Haug, PhD student at our Faculty of Agricultural, Environmental and Food Sciences won the Young Minds Award for the best oral presentation for her study on this topic at the XIII International Symposium on Integrating Canopy, Rootstock, and Environmental Physiology in Orchard Systems, organised by the International Society for Horticultural Science (ISHS).
The study she presented, entitled “Physiological responses of apple trees on three rootstocks to decreasing water supply”, focuses on the selection of rootstocks that improve drought resistance and optimise water use. It is in fact common practice to use rootstocks to grow apple trees. The rootstock is the part of the tree that goes from the base of the trunk to the bottom of the entire root system and is the point at which a particular variety is grafted. The upper part of the tree, which is grafted onto the rootstock, determines the variety (type) of apple, while the rootstock, the lower part, is important for maintaining the size and the quality of the fruit. Anna-Lena’s study also shows the importance of the rootstock in withstanding adverse environmental conditions, such as drought: by testing different rootstocks, she was able to show differences in their ability to cope with water deficits.
Her study, carried out under the supervision of Prof. Massimo Tagliavini of unibz and in collaboration with Martin Thalheimer of the Laimburg Research Centre, represents a promising strategy for ensuring sustainable fruit production under increasingly challenging environmental conditions.